A home inspection provides you with information regarding the condition and functionality of different systems inside and outside the home. The heating or heating/cooling system is part of the inspection. One of the most common heating systems in the United States and Canada is the forced-air furnace. In a forced-air furnace, oil or gas is used to heat a piece of metal. A fan pushes the warmed air into a series of ducts, which carry it throughout the house. The cold-air return feeds air back into the system. The following is a list of six common forced-air furnace problems and five common problems in a combined heating/cooling HVAC unit:
1. Electrical issues. Electrical service to the home may not be adequate for the heating/cooling system. This could mean a blown fuse or tripped breaker during heavy use. An electrical kill switch should be located near the heating unit so the power can be cut off in case of an emergency.
2. Dirty/clogged filter. Filters were originally designed to keep mechanical elements free from dirt and dust. Today, filters are designed to help clean the air while the equipment is running. If the filter is not changed or cleaned regularly, it can block sufficient air flow and cause problems with heating and cooling functions.
3. Cracks/breaks in ductwork. Improperly installed air ducts, or cracked or broken connections between ducts, can cause the heated or cooled air to vent into attics or walls instead of into the intended rooms.
4. Blocked/closed registers. Furniture, boxes or drapery may be blocking the register in certain rooms. This disrupts the flow of heat.
5. Old/unmaintained system. Heating and cooling systems operating longer than their design life can cause health or safety issues. Gas-fired appliances, including furnaces, must have a properly operating exhaust system to vent the byproducts of combustion, including carbon monoxide, a potentially harmful gas, outside. Cracked heat exchangers and other problems could cause these gases to leak into the home.
6. Poorly installed flue pipes. The flue moves the exhaust gas, created during combustion, from the heating unit to the outside, or to a chimney that vents outside. This flue, or vent pipe, must be kept away from all flammable materials, be properly supported and slope up on its way to the outdoor vent or chimney.
1. Dirty/clogged condenser coils. Restricting air flow to the outdoor condenser unit can lead to poor heat transfer. All foliage or obstructions should be cut back at least 1 foot around the outdoor condenser unit. The fin surface of the evaporator coil can be cleaned using a brush or vacuum.
2. Uneven condenser unit pad. The outside unit should be within 10 degrees of level. If it is not level, it can reduce the effectiveness of lubrication in the tubing or increase stress on refrigerant lines.
3. Leaks. The indoor portion of an air conditioner can be installed in a basement, closet or attic. A drain hose is used to remove the condensation that collects during the cooling process. If the drain hose becomes clogged, then water will eventually back up and spill over onto the floor.
4. Unable to inspect due to weather. Temperatures must be warm enough to turn on the air conditioning unit. Turning on the unit when temperatures are too low can cause extensive damage. If the inspector is unable to check the functionality of the air conditioner, then it should be noted in the written report.
5. Missing insulation. Two pipes carry refrigerant between the evaporator and condenser coils. The larger one, carrying the cool gas, should be insulated. This prevents the line from sweating indoors, causing water damage, and improves efficiency by keeping the line cool.
Because of the health and safety issues involved, it is important to maintain your heating/cooling systems. Have your furnace and air conditioner inspected by a licensed technician at least once a year.
For more information on the systems assessed during a home inspection, click here.